Viewing content such as text, images, and graphics, on mobile content display devices such as smartphones, netbooks, gaming devices, PDAs, and laptop computers has become increasingly ubiquitous among users. Many of these mobile devices have a relatively small screen size (e.g., as compared to desktop computer displays), and as a consequence, the content that is displayed on these mobile devices is often presented in a relatively small size to fit the content on a display. And because content display devices are used for many functions (e.g., navigation, web browsing, reading) and are so easily moved, often times the size of text that is presented is less than ideal.
Although some content display devices enable a user to manually adjust a size of content (e.g., by increasing the size of content to see more detail or decreasing the size to see a wider range of content). The adjustment of content, however, often requires negotiating multiple menu layers to adjust content, or finger gestures that require motions that may be inconvenient to carry out. And in many environments (e.g., within an automobile or engaged in other activities that occupy the user's hands) it is very difficult or impossible to safely or quickly adjust content size. Accordingly, currently available content display devices operate in a less-than-ideal manner and will most certainly not be satisfactory in the future.